Thoratec warns heart device users to check battery expiration date

2 deaths reported when patients filed top switch system fast enough

Pleasanton-based Thoratec Corporation has issued a voluntary Urgent Medical Device Correction Letter to all hospitals who have patients supported with its HeartMate II LVAS reminding them to monitor the expiration date of the the system's backup battery.

An HeartMate II is a mechanical device that helps people when their heart is too weak to pump blood. Although it doesn't replace the heart, it assists in pumping oxygen-rich blood throughout the body so that the organs and muscles can function properly. The system has parts that work inside and outside the body.

Inside, the heart pump is attached to the left side of the heart. Outside, a controller, batteries, and driveline help to power and control the heart pump. A backup battery has a 36 month expiration date which, if allowed to expire, triggers an advisory alarm, indicated by a yellow wrench symbol.

Thoratec representatives said they had recently received reports of patients experiencing advisory alarms for expired backup batteries. Some of these patients attempted to switch from their primary to a backup System Controller, and of those, three were unable to connect their pump to their backup system in a timely manner, resulting in two patient deaths and one serious injury.

The Urgent Medical Device Correction Letter is intended to prevent the occurrence of certain preventable advisory alarms that may result in patients deciding to attempt a System Controller exchange, the company said.

Thoratec is working with hospital staff to identify patients that may be close to reaching the 36-month expiration date of their backup battery in order to make a priority replacement.

The company said that patients with a HeartMate II LVAS with the serial number starting with the letters "EPC" are not affected by warning and need to take no action.

Patients with questions should contact their doctor or HeartMate II coordinator at their hospital. Clinicians with questions should contact their Thoratec representative or call Thoratec's 24-hour HeartLine at 1-800-456-1477.